Ventilating a patient using a bag valve and a face mask is not easy to perform, especially for a long period of time, and mandates experience and strength by the care giver. The need for a tight seal around the mouth and nose is a major challenge especially if the patient has a beard. Nevertheless, the face mask is the only approved respiratory support that medics and other basic care givers are allowed to use in the out-of-the-hospital setting, and only physicians and paramedics are allowed to use more advanced techniques, providing a definite airways. Thus, despite its lower effectiveness, the bag valve mask technique is the most commonly used in the field